Knowledgebase

Items
Core & CoreTrend Files: Getting Started
New Version of Core 2009 PC Released 2/19/2012 - Name and Address Updates
Why are there duplicates when I combine Core File years to create a database for trend analysis?
Core 1998 PC File: LEGEXP (Schedule A, Part III, L1: lobbying expenses). (Technical Note).
Core 2008 Variables - Inconsistent Values for Returns Ending >= 200812 (New Form 990)
Core file circa periods - definition and background
Core Private Foundations file: Field Names for 2001 IRS F990PF
Core Public Charities & Non-c3 file: Form 990 with Field Names (Helpful Hint)
Core Public Charities and Non-c3 file: Field Names for 1996 IRS F990
Creating and Verifying Core File Data
Missing Core "C-Other" Files in the early 1990s are missing some names, states, and zipcodes (Technical Note)
NCCS Core Supplement (aka: Super Core)
New Form 990 Revisions Effective Tax Years 2008 and Later - Impact on NCCS Data Files and Research
Core Files: Assessing Their Accuracy & Building a Longitudinal File for Trend Analysis (Technical Note / Method Note)
Core(PF)- SOI variable crosswalk (Helpful Hint)
Data issues in the 501(c) "other" Core files (Technical Note)
RTF special extracts (Technical Note)
Start and fiscal years (STYEAR and FISYR) in the Core files (Technical Note)
Where is the Core 1993 PF File? (FAQ)